From 9bb218828c8f4fa6587af93e248903c96ce469d0 Mon Sep 17 00:00:00 2001
From: Markus Pargmann <mpa@pengutronix.de>
Date: Fri, 26 Dec 2014 12:41:18 +0100
Subject: [PATCH] batman-adv: debugfs, avoid compiling for !DEBUG_FS

Normally the debugfs framework will return error pointer with -ENODEV
for function calls when DEBUG_FS is not set.

batman does not notice this error code and continues trying to create
debugfs files and executes more code. We can avoid this code execution
by disabling compiling debugfs.c when DEBUG_FS is not set.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
---
 net/batman-adv/Makefile  |  2 +-
 net/batman-adv/debugfs.c |  8 --------
 net/batman-adv/debugfs.h | 34 ++++++++++++++++++++++++++++++++++
 3 files changed, 35 insertions(+), 9 deletions(-)

diff --git a/net/batman-adv/Makefile b/net/batman-adv/Makefile
index 79833ebcc2dd..bd7e343c98d1 100644
--- a/net/batman-adv/Makefile
+++ b/net/batman-adv/Makefile
@@ -20,7 +20,7 @@ obj-$(CONFIG_BATMAN_ADV) += batman-adv.o
 batman-adv-y += bat_iv_ogm.o
 batman-adv-y += bitarray.o
 batman-adv-$(CONFIG_BATMAN_ADV_BLA) += bridge_loop_avoidance.o
-batman-adv-y += debugfs.o
+batman-adv-$(CONFIG_DEBUG_FS) += debugfs.o
 batman-adv-$(CONFIG_BATMAN_ADV_DAT) += distributed-arp-table.o
 batman-adv-y += fragmentation.o
 batman-adv-y += gateway_client.o
diff --git a/net/batman-adv/debugfs.c b/net/batman-adv/debugfs.c
index 0c213a892296..46118084221a 100644
--- a/net/batman-adv/debugfs.c
+++ b/net/batman-adv/debugfs.c
@@ -482,11 +482,7 @@ rem_attr:
 	debugfs_remove_recursive(hard_iface->debug_dir);
 	hard_iface->debug_dir = NULL;
 out:
-#ifdef CONFIG_DEBUG_FS
 	return -ENOMEM;
-#else
-	return 0;
-#endif /* CONFIG_DEBUG_FS */
 }
 
 /**
@@ -541,11 +537,7 @@ rem_attr:
 	debugfs_remove_recursive(bat_priv->debug_dir);
 	bat_priv->debug_dir = NULL;
 out:
-#ifdef CONFIG_DEBUG_FS
 	return -ENOMEM;
-#else
-	return 0;
-#endif /* CONFIG_DEBUG_FS */
 }
 
 void batadv_debugfs_del_meshif(struct net_device *dev)
diff --git a/net/batman-adv/debugfs.h b/net/batman-adv/debugfs.h
index f3b49c394446..ed25605ca732 100644
--- a/net/batman-adv/debugfs.h
+++ b/net/batman-adv/debugfs.h
@@ -20,6 +20,8 @@
 
 #define BATADV_DEBUGFS_SUBDIR "batman_adv"
 
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+
 void batadv_debugfs_init(void);
 void batadv_debugfs_destroy(void);
 int batadv_debugfs_add_meshif(struct net_device *dev);
@@ -27,4 +29,36 @@ void batadv_debugfs_del_meshif(struct net_device *dev);
 int batadv_debugfs_add_hardif(struct batadv_hard_iface *hard_iface);
 void batadv_debugfs_del_hardif(struct batadv_hard_iface *hard_iface);
 
+#else
+
+static inline void batadv_debugfs_init(void)
+{
+}
+
+static inline void batadv_debugfs_destroy(void)
+{
+}
+
+static inline int batadv_debugfs_add_meshif(struct net_device *dev)
+{
+	return 0;
+}
+
+static inline void batadv_debugfs_del_meshif(struct net_device *dev)
+{
+}
+
+static inline
+int batadv_debugfs_add_hardif(struct batadv_hard_iface *hard_iface)
+{
+	return 0;
+}
+
+static inline
+void batadv_debugfs_del_hardif(struct batadv_hard_iface *hard_iface)
+{
+}
+
+#endif
+
 #endif /* _NET_BATMAN_ADV_DEBUGFS_H_ */
-- 
2.20.1